Method of improving dielectric performance of alumino-borosilicate glass

Abstract

A method of improving dielectric performance of alumino-borosilicate glass includes heating the glass to a heated temperature of at least 400° C. and less than 1200° C. keeping the glass at the heated temperature for at least 30 minutes, followed by cooling the glass to a cooled temperature of 40° C. over at least 2 hours. In terms of constituents, the glass includes SiO2, Al2O3, B2O3, MgO, and CaO. After the cooling. the glass has a dielectric loss tangent no greater than 0.0020.

1 . A method of improving dielectric performance of alumino-borosilicate glass, comprising:
 heating the glass to a heated temperature of at least 400° C., wherein the heated temperature is less than 1200° C., and wherein, in terms of as-analyzed constituents, the glass comprises:
 at least 60 mol % to 75 mol % SiO 2 ; 
 at least 2 mol % to 9 mol % Al 2 O 3 ; 
 at least 15 mol % to 25 mol % B 2 O 3 ; 
 at least 1 mol % to 6 mol % MgO; and 
 at least 1 mol % to 5 mol % CaO; and 
   keeping the glass at the heated temperature for at least 30 minutes; and   cooling the glass from the heated temperature to a cooled temperature of 40° C., over at least 2 hours.   
     
     
         2 . The method of  claim 1 , wherein after the cooling, the glass has a Df no greater than 0.0020. 
     
     
         3 . The method of  claim 1 , wherein the heated temperature is at least 600° C. 
     
     
         4 . The method of  claim 1 , wherein the cooling occurs over at least 4 hours, and wherein the keeping is for at least 2 hours. 
     
     
         5 . The method of  claim 1 , wherein, prior to the heating, the glass has been formed as a sheet. 
     
     
         6 . A method of improving dielectric performance of alumino-borosilicate glass, comprising:
 forming the glass into a sheet; wherein, in terms of as-analyzed constituents, the glass of the sheet comprises:
 at least 60 mol % to 75 mol % SiO 2 ; 
 at least 2 mol % to 9 mol % Al 2 O 3 ; 
 at least 15 mol % to 25 mol % B 2 O 3 ; 
 at least 1 mol % to 6 mol % MgO; and 
 at least 1 mol % to 5 mol % CaO; and 
   keeping the sheet at the heated temperature for at least 30 minutes; and   cooling the sheet from a heated temperature to a cooled temperature of 40° C., over at least 2 hours, and wherein the heated temperature is at least 400° C.   
     
     
         7 . The method of  claim 6 , further comprising bonding electronics to the sheet. 
     
     
         8 . The method of  claim 7 , wherein the bonding is after the cooling. 
     
     
         9 . The method of  claim 6 , wherein after the cooling, the sheet has a Df no greater than 0.0020. 
     
     
         10 . The method of  claim 6 , wherein the heated temperature is at least 600° C. 
     
     
         11 . The method of  claim 10 , wherein the heated temperature is less than 1000° C. 
     
     
         12 . The method  claim 6 , wherein the cooling occurs over at least 4 hours, and wherein the keeping is for at least 2 hours. 
     
     
         13 . A method of improving dielectric performance of alumino-borosilicate glass, comprising:
 forming a glass into a sheet, wherein, in terms of as-analyzed constituents, the glass comprises:
 at least 60 mol % to 75 mol % SiO 2 ; 
 at least 2 mol % to 9 mol % Al 2 O 3 ; 
 at least 15 mol % to 25 mol % B 2 O 3 ; 
 at least 1 mol % to 6 mol % MgO; and 
 at least 1 mol % to 5 mol % CaO; 
   heating the sheet to a heated temperature of at least 400° C., wherein the heated temperature is less than 1200° C.; and   cooling the sheet from the heated temperature to a cooled temperature of 40° C.   
     
     
         14 . The method of  claim 13 , wherein the glass more specifically comprises less than 7.5 mol % Al 2 O 3 , greater than 16 mol % B 2 O 3 , and less than 5.5 mol % MgO. 
     
     
         15 . The method of  claim 13 , wherein after the cooling, the sheet has a Df no greater than 0.0020. 
     
     
         16 . The method of  claim 13 , wherein the heated temperature is at least 600° C. 
     
     
         17 . The method of  claim 13 , wherein the cooling occurs over at least 4 hours. 
     
     
         18 . A method of improving dielectric performance of alumino-borosilicate glass, comprising:
 heating the glass to a heated temperature of at least 400° C., wherein the heated temperature is less than 1200° C., and wherein, in terms of as-analyzed constituents, the glass comprises SiO 2 , Al 2 O 3 , B 2 O 3 , MgO; and CaO;   keeping the sheet at the heated temperature for at least 30 minutes; and   cooling the glass from the heated temperature to a cooled temperature of 40° C. over at least 2 hours,   wherein after the cooling, the glass has a Df no greater than 0.0020.   
     
     
         19 . The method of  claim 18 , wherein, prior to the heating, the glass has been formed as a sheet. 
     
     
         20 . The method of  claim 19 , further comprising bonding electronics to the sheet after the cooling.